The purpose of this research is to develop a device to aid in the investigation of a novel procedure for the long-term cryopreservation of organs. The preservation procedure involves the utilization of ultrahigh hydrostatic pressure (i.e. about 6300 atmospheres) during the freezing and thawing process. The integration of this approach with modified existing protocols for cryopreservation is anticipated. The apparatus will have the capability to apply hydrostatic pressures on the order of 6300 atmospheres in intervals as short as .1 second as well as indefinitely longer periods, and maintain such pressures as long as desired. Temperature will be independently controllable ranging to below -150 C. The chamber will accommodate a sample of about 2 cm diameter and 8 cm long. The performance evaluation will be carried out to fully characterize the operating range and to establish the necessity for any modifications of a final commercial model. Several tissue samples will be processed using relatively simple protocols. These samples will be examined for evidence of the effectiveness of the ultrahigh pressure technique.